Novel clamp boosts coupling torque capacities

A clamp hub is usually the best way of attaching a coupling to a shaft, because it allows fine adjustment of the coupling position and protects the shaft from damage. But it is not always possible to use such a hub. In some installations, engineers are forced to use set-screw attachments to boost the system`s torque capacity — even though the screws can damage the shaft and make it difficult to maintain.

Reliance Gear has investigated the problem and come up with a new design of clamp hub which, it says, can achieve the same rated torque as set-screw couplings.

The Reliance engineers carried out deflection analyses on traditional single-slot clamp designs and found that they produced just two areas of high interface pressure during clamping. The engineers concluded that if they could reduce the bore clearance cleanly and evenly, they could prevent slippage, even in high-torque applications.

To achieve this, they developed a clamp with a cross-slit design which, they say, produces a consistent pressure around the whole of the interface between the shaft and the clamp. They have applied for a patent for this new design which, they claim, can produce the same rated torque as set-screw couplings.

Reliance is now offering the new clamping system on its Reli-a-Flex one-piece couplings.